they need to develop final disposal sites in broader areas as a final measure after having decreased the number of facilities to be managed, and taken certain and high-level environment-conserving measures as well as reducing the amount of wastes and thoroughly promoting appropriate recycling and reuse of wastes.

Municipalities need to develop waste treatment facilities needed for the establishment of such a sound material-cycle society after having established specific goals related to the 3Rs of wastes and having formulated a definite plan of comprehensive measures for achieving the goals.

### B. Industrial Waste

The residual volume of final disposal sites for industrial wastes at the end of fiscal 2006 is 16,286 m $ ^{3} $ , a decrease of 2,339 m $ ^{3} $ . In addition, the national average residual number of years is 7.5, which indicates the situation has gradually improved. However, the residual number of years in the Greater Tokyo Metropolitan area is 4.4, and, in greater metropolitan areas in particular, their residual number of years has been decreasing (Figure 2-44).

Basically, final disposal sites of industrial wastes should be developed by private business operators. However, based on the development situation, the final disposal volume regarded as necessary needs to be secured with the development of facilities by the public sector.

## (2) Efforts at Thermal Recycling in Waste Incinerators

### A. Use of Residual Heat from Waste Incineration

About 70% of all facilities around the country make effective use of residual heat from waste incinerators for hot water, steam, electric power generation, etc (Figure 2-45). More specifically, the residual heat is used for various purposes, such as waste power generation described later, heating and hot water supply in waste incinerators. The heat is also used in places other than waste incinerators for heated pools, supply of hot water and heat to social welfare organizations, such as welfare facilities for the elderly, regional heating, etc.

Saving of natural resources and energy used in waste disposal facilities and contribution to regional communities account for the majority of reasons for using residual heat.

In addition to the promotion of such use of residual heat in waste incinerators, a system for further promoting the supply of heat, etc. to places other than waste incinerators needs to be created. In order to develop such a system, technical problems, such as dealing with changes in the volume and quality of wastes, cost comparison with heat supplied by gas and petroleum, coordination with relevant laws and regulations, such as the Electricity Enterprises Law, and so forth need to be fully examined.

### B. Waste Power Generation

In waste power generation, the thermal energy of high-temperature exhaust gas generated when wastes are incinerated is collected by a boiler, which generates steam to rotate a turbine for electric power generation. Waste power gener-

Figure 2-44 Changes to residual volume and remaining years of final disposal sites (industrial waste)

Source: Ministry of the Environment

Figure 2-45 Waste heat utilization of incinerators (fiscal year 2006)

State of waste heat utilization	Utilized	Not utilized
Utilization of warmwater	Utilization of steam	Power generation	Others
Warm-water: inside facilities	Warm-water: outside facilities	Steam: inside facilities	Steam: outside facilities	Power generation: inside facilities	Power generation: outside facilities
Number of facilities	877 (904)	812 (840)	264 (273)	235 (230)	103 (102)	292 (285)	186 (179)	63 (62)	424 (414)

Figures in the brackets are data for fiscal year 2005.

Note 1: Apart from private facilities, the facilities shown in the graph are established by municipalities or affairs associations, and include facilities for which construction work started in the relevant year and facilities out of service, but exclude closed facilities. Source: Ministry of the Environment

ation is one of the effective ways of using residual heat from waste incinerators.

At the end of fiscal 2006, among waste incinerators in operation or under construction, 293 incinerators are generating electrical power or scheduled to do so (Table 2-3). In addition, larger-scale waste incinerators tend to conduct waste power generation. Therefore, while such incinerators account for 22.5% of all incinerators, their waste treatment capability accounts for about 56.0% of that of all waste incinerators. The total amount of generated electricity of the waste incinerators conducting waste power generation is about 7.2 billion kWh. When annual electric power consumption per household is calculated as 3,600 kWh, the total amount equals to the annual electric power consumption of about two million households. In addition, 186 waste incinerators use electric power generated with waste power generation in places other than their facilities.